The mRNA levels of VDR and CaSR will be estimated by Real-PCR (Stratagene Robocycler Gradient 40 system) using specific primer sequences and PCR conditions. The PCR products will be separated by electrophoresis on 6% agarose gel; the products will be then stained with ethidium bromide and located by fluorescence using UV light. Bio Max 1D TM 1.5.1 (Kodak, Rochester, NY) would be used to evaluate the band intensities of the PCR bands.